1. Field of the Invention
The present invention relates to dome switches suitable for use in electronic devices.
2. Description of the Related Art
Dome switches are well-known and often used in consumer electronic products to implement buttons. For example, various consumer electronic devices, e.g., a mobile telephone, a personal digital assistant, game controller, or remote controller, typically include a plurality of buttons that a user can press to invoke various operations with respect to such devices. Such buttons can, for example, be used for function (e.g., send, end, navigate, etc.) buttons or for buttons of an alphanumeric keypad/keyboard. These buttons in many cases are implemented by dome switches.
A dome switch consists of a dome made from metal or plastic that can be deformed temporarily by a user press to invoke a switching action. Then, when the user press is removed, the dome returns to its original, undeformed shape. Today, with many electronic devices, proper operation of buttons is an important requirement for usability and user satisfaction. With respect to dome switches, the tactile feedback provided by dome switches is often very helpful to users of the consumer electronic products. However, conventional assembly of such buttons implemented by dome switches is inefficient and complicated. Generally, a dome must be placed on a substrate and corresponding structures often provide a button or key structure (with or without an actuation nub) that can be pressed downward to engage the dome during a button or key press. In some designs, activation nubs are provided on the button or key structure or on the peaks of the domes themselves. In any case, the formation of the activation nubs is a separate manufacturing step that is tedious and time-consuming. In addition, the placement of the actuation nubs relative to the domes is not always as accurate as desired. For example, if the actuation nub does not properly align with the center region of a dome, the tactile feedback for such dome switch will be disturbed and therefore not as robust as intended.